As American children play team sports in greater numbers and with growing intensity, their risk of getting a concussion has grown but the science of preventing, diagnosing and treating this increasingly frequent brain injury remains maddeningly incomplete, a group of experts warned Wednesday. Although mounting concern over traumatic brain injury has spawned high-tech imaging techniques, helmet-mounted accelerometers and sideline concussion tests, these have yet to show they can reduce sports-related concussions, the Institute of Medicine concluded in a 286-page report.

Deion Sanders is far from the only present-day employee of the National Football League to have filed a workers' compensation claim in California claiming head or brain injuries. At least 43 present-day assistant coaches and front office personnel who previously played in the league have filed claims against their former teams in the last half-dozen years, records show . In addition, more than six television analysts for NFL Network, which is owned by the league, have made such claims.

Brain-damaged Ann Marie Degree, 38, has spent half her life in locked psychiatric facilities because she has virtually no control over her impulses, and her family says she will probably spend the rest of her life in such places. But first the Riverside County district attorney's office wants her to spend a year behind bars.

On July 11, 1988, Claudia L. Osborn, a Detroit doctor, was hit by a car while riding her bicycle. At first it was believed that her initial cognitive difficulties were a normal part of the healing process. As it turns out, the accident had caused profound brain trauma. In "Over My Head: A Doctor's Own Story of Head Injury From the Inside Looking Out," Osborn, 43, chronicles the process of rehabilitation, recovery and finding a new life. Here, the prologue: March 8, 1989 NEW YORK Hello. . . .

In the year after a traumatic brain injury, roughly half of survivors will likely experience a bout of clinical depression — a rate almost eight times higher than that found in the general population, a study published Tuesday in the Journal of the American Medical Assn. has found. And those whose head trauma was followed by depression reported significantly more pain, greater mobility problems and more difficulty carrying out their usual responsibilities than those who were not plagued by post-injury depression.

At a community hospital here, doctors and therapists are working to help Marines overcome what is often called the signature injury of the Iraq war: brain trauma with no visible wounds. "It's the silent injury," said Jessica Martinez, an occupational therapist at Scripps Memorial Hospital Encinitas. "With every blast they suffer, their brain is rattling like a yolk in an egg." Marine Lance Cpl. Brian Vargas was a high school football player.

An Orange County sheriff's deputy described by colleagues as a hard-working family man lay in critical condition Monday after an elderly motorist drove through a red light in Aliso Viejo and broadsided his motorcycle, sending him hurtling more than 60 feet through the air. Deputy Steve Edward Parsons, the father of two small children and a 10-year department veteran, suffered serious brain trauma and an array of broken bones in the 10:18 a.m. crash, officials said. "It was very bad.

One thing about a place that looks like a saloon: It can bring out the ornery in people. But the arguing this week inside a long-shuttered restaurant heralds a new beginning for Integrity House. By the end of the month, the Fullerton nonprofit organization for people with brain trauma and developmental disabilities will move into the former Viva Mexico, ending a desperate, months-long search for a few thousand square feet of real estate.

The number of children in the U.S. seeking emergency medical care for concussions incurred playing competitive sports more than doubled in the five years leading up to 2005, according to a study published Monday in the journal Pediatrics. Much of that increase came not from high school athletes who have been the mainstay of emergency-room visits for concussions, but from middle-schoolers and even elementary school students who have flocked to play on elite travel teams and in competitive youth leagues across the country.

A Northern California nursing home has been fined $100,000 after its staff allegedly failed to prevent a patient from falling twice and suffering a fatal head injury for which he was not treated, state public health officials announced recently . The 85-year-old patient, who had a heart condition and diabetes, was supposed to use a walker and be supervised when walking, according to a state investigator's report released Aug. 3 on ...